...
What I'm hoping for is that there is a way for the ARIN TAL to be
included in software distributions, without compromising ARIN's legal
position.

Perhaps an exception for software distributors would already go a long
way?

   "You can include the ARIN TAL in your software distribution as long
   as you also include an unmodified copy of the
   https://www.arin.net/resources/rpki/rpa.pdf file alongside it."

Kind regards,

While not exactly what you seek, we can get a bit closer to the goal – i.e. by eliminating the need for the user installing a software package to first go get the ARIN TAL and put it in the right place prior to running the installation software.

To that end, the ARIN TAL page <https://www.arin.net/resources/rpki/tal.html> has been revised with specific guidance –

Software Installation Tools

Software installation tools may download the ARIN TAL on behalf of a user after the user has confirmed their acceptance of the ARIN Relying Party Agreement (RPA) on the ARIN website. This acceptance must require "agreement to the ARIN Relying Party Agreement (https://www.arin.net/resources/rpki/rpa.pdf)" and obtain a non-ambiguous affirmative action by clicking on, or the entry of, a word of agreement (such as "yes" or "accept")

Example:

Attention: This package requires the download of the ARIN TAL and agreement to the ARIN Relying Party Agreement (RPA) (https://www.arin.net/resources/rpki/rpa.pdf).

Type "yes" to agree, and you can proceed with the ARIN TAL download: yes

We will continue to explore mechanisms for making ARIN’s RPKI repository more accessible to the community, but felt that this interim step could be accomplished promptly and was worth noting in a timely manner to those distributing RPKI software.